Idea for TW: "Demo Gold Club"

my local tennis store has a nice program where you pay a yearly membership fee and then you get free demo's and stringing for the year.
Why doesn't TW do something similar? For example, for say $50 per year, you get free demos that you can keep for a max of 1 week at a time.
Or for $100 per year...you get free demos PLUS free stringing?